銀河の塊状分布は,X線観測で検出できるのか?
1Astronomy Department, University of California, Berkeley, California 94720, USA.
Nature
|July 7, 1972
まとめ
公開されたX線望遠鏡のデータは,源のクラスタリングによる背景放射表面の明るさの変動を明らかにすることはできません. 現在の観測では,これらの微妙な宇宙構造と,その宇宙X線背景への影響を検出するための感度が不足しています.
科学分野:
- コスミック・マイクロ波・バックグラウンド・放射線
- 銀河外天文学 銀河外天文学
- X線天文学 X線天文学
背景:
- 宇宙X線背景 (Cosmic X-ray background,CXB) は,解明されていない多数の源からのX線放射の拡散した輝きである.
- CXB表面の明るさの空間的変動を理解すると,これらのソースの分布とクラスタリングの洞察が得られます.
- 以前の研究では,X線望遠鏡のデータに基づいてCXBを調査しましたが,限界があります.
研究 の 目的:
- 宇宙X線背景の表面明るさの変動を検出するために,既存の公開X線望遠鏡データの適切性を評価する.
- 現在のデータがCXBに寄与するソースクラスタリングまたはスーパークラスタリングの証拠を明らかにできるかどうかを判断する.
主な方法:
- 公開されているX線望遠鏡の観測データの分析.
- CXB内の表面の明るさの変動に関する統計的調査.
- 観測された変動の比較と,ソースクラスタリングの理論的予測.
主要な成果:
- 公開されたX線望遠鏡のデータは,ソースクラスタリングによって引き起こされる表面明るさの変動を解決するのに不十分です.
- 現在の計器の感度では,X線発射器の大規模構造に起因する微妙な変化を検出することができません.
- 既存のデータセットは,CXBに影響を与える重要なソーススーパークラスタリングの存在を確認または否定することはできません.
結論:
- 現在のX線観測データは,CXB表面の明るさの変動を通して,X線源のクラスタリング特性を研究するのに不十分です.
- 感度が向上した将来のX線ミッションは,これらの小規模な構造と,宇宙X線背景へのそれらの貢献を調査する必要があります.
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